Scratch that...

PerlBrew has a bug(85493) noted in version 0.63 which has never been addressed. I spent a good 2.5 hours trying to figure out why 'perlbrew list-modules' didn't return anything. Finally found the answer at RT CPAN In simple terms: list-modules will not work if you are use'ing or have switch'ed to an alias. You must use the full name of the Perl dist you are using as is shown in 'perlbrew list' or 'perlbrew available'. Found a workaround which has been added to PerlBrew (perlbrew list-modules), though I have yet to try it.

Get modules from one version of perl to anotherperlbrew list-modules | perlbrew exec --with perl-5.16.0 cpanm